Atwell said the store is "here just to raise money for our programs," and it isn't going to pay an expert to determine if the work is authentic. He said the store will instead let people bid for the piece and determine its value on their own.

As of Monday afternoon, bidding had climbed to $550.

Mark Winter of Art Experts Inc. in Daytona Beach, Florida, which appraises and authenticates artwork, said it's possible the piece in Grand Junction is real because it's numbered. If it is real, Winter said, it could be worth $2,000 to $3,000.

But he said there are also more than 200,000 fake Dali lithographs floating around — and there's a market for them too.